Differences in Flavor Quality of Vine Teas Processed by Different Techniques

In order to systematically reveal the differences in flavor quality among green, yellow and black vine teas, processed from the young stems and leaves of Ampelopsis grossedentata by different techniques, sensory evaluation, physicochemical analysis and headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography-mass spectrometry (GC-MS) were used to analyze the quality of green, yellow and black vine teas. Sensory evaluation results showed that yellow vine tea was covered by a silver white powder, and its infusion had a bright yellow color, strong fruity aroma and mellow taste; green vine tea had a yellowish-green color, and its infusion had a bright greenish-yellow color, strong stir-fried aroma and slightly bitter taste; black vine tea had a reddish-brown color, and its infusion had a bright orangered color, strong floral and fruity aroma, and mellow taste. Taste composition analysis showed that the contents of soluble sugar, water extract, and dihydromyricetin were all higher in green vine tea than in yellow and black vine teas, while the content of free amino acids in black vine tea was the highest. A total of 56 volatile components were identified in the three vine teas, with hydrocarbons being dominant in green and yellow vine teas while alcohols being dominant in black vine tea. 1,1,6-trimethyl-1,2-dihydronaphthalene, stigmasterol, lauryl alcohol and linalool were closely related to the stir-fried aroma of green vine tea, while phenylacetaldehyde, naphthalene, 2-pentylfuran, P-umbelliferyl hydrocarbons, and n-tetradecane were closely related to the fruity aroma of yellow vine tea, and phenylacetaldehyde, methyl salicylate, 1,1,6-trimethyl-1,2-dihydronaphthalene contributed to the floral and fruity flavor of black vine tea.